US3824800A - Air conditioning unit and control - Google Patents

Air conditioning unit and control Download PDF

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Publication number
US3824800A
US3824800A US00395081A US39508173A US3824800A US 3824800 A US3824800 A US 3824800A US 00395081 A US00395081 A US 00395081A US 39508173 A US39508173 A US 39508173A US 3824800 A US3824800 A US 3824800A
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US
United States
Prior art keywords
air
conditioned
supply duct
port
control signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00395081A
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English (en)
Inventor
R Church
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Carrier Corp
Original Assignee
Carrier Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to US00395081A priority Critical patent/US3824800A/en
Application filed by Carrier Corp filed Critical Carrier Corp
Publication of US3824800A publication Critical patent/US3824800A/en
Application granted granted Critical
Priority to GB3456774A priority patent/GB1454199A/en
Priority to ZA00745055A priority patent/ZA745055B/xx
Priority to IT26343/74A priority patent/IT1019971B/it
Priority to CH1117274A priority patent/CH574587A5/xx
Priority to AU72453/74A priority patent/AU476323B2/en
Priority to DE2442102A priority patent/DE2442102C3/de
Priority to FR7430138A priority patent/FR2243394B1/fr
Priority to BR7434/74A priority patent/BR7407434D0/pt
Priority to SE7411295A priority patent/SE408585B/sv
Priority to JP49102847A priority patent/JPS5216343B2/ja
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/02—Ducting arrangements
    • F24F13/06—Outlets for directing or distributing air into rooms or spaces, e.g. ceiling air diffuser
    • F24F13/072—Outlets for directing or distributing air into rooms or spaces, e.g. ceiling air diffuser of elongated shape, e.g. between ceiling panels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
    • F24F11/74—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity
    • F24F11/76—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity by means responsive to temperature, e.g. bimetal springs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F3/00—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
    • F24F3/044—Systems in which all treatment is given in the central station, i.e. all-air systems

Definitions

  • An air conditioning unit for supplying conditioned air from a central station into a space to be conditioned to cool the space.
  • the unit includes a device to regulate the quantity of air discharged therefrom.
  • a pressure responsive valve is connected to the device and to the supply duct to provide a control signal to the device, the magnitude of the control signal varying with changes in pressure of the conditioned air in the supply duct to the unit.
  • the unit further includes a thermostat for further varying the control signal supplied to the device, the magnitude of the control signal being varied in accordance with changes of the temperature in the area being conditioned.
  • a suitable control has a normally open port through which conditioned air passes from the supply duct to the pressure responsive valve, and a normally closed port communicating with the thermostat.
  • the nonnally closed port is opened when the temperature of the conditioned air supplied from the central station exceeds a predetermined value to pass the relatively warm air through the port'to the thermostat, the magnitude of the control signal thereafter passing from the pressure responsive valve to the air regulating device being determined solely by the pressure of the conditioned air in the supply duct.
  • This invention relates to air conditioning units, and more particularly to a control therefor.
  • the air conditioning unit disclosed in the abovecited US. Pat. can deliver a relatively constant quantity of conditioned air regardless of changes in the supply air pressure, there are many applications in which it may be desirable to reduce the quantity of air discharged from a unit in accordance with variations in changes in the temperature of the space being served thereby. Accordingly, many of the units include a thermostat for sensing the temperature of the air and for further providing a control signal to the air quantity regulating means of the unit to reduce the quantity of air delivered therefrom as the temperature of the space approaches a desired level.
  • the air discharged from each of the units compensates for heat developed in the various areas served thereby from among any or all of the following: lights, electric machines, occupants, and solar heat developed via radiation and conduction.
  • warm-up switches To compensate for such overcooling, some systems employing units of the type heretofore discussed, have included warm-up switches.
  • the central station equipment instead of cooling the air, warms the air to a relatively high temperature level before it is delivered to the various rooms.
  • the warm-up switch senses the flow of the relatively warm air in the supply duct and overrides the normal thermostatic control to deliver the maximum quantity of air from thhe unit in accordance with predetermined levels.
  • the temperature level in the rooms may be readily and rapidly increased to satisfactory levels before the occupants thereof arrive, eliminating occupant dissatisfaction due to excessively low temperature levels.
  • warm-up switches have heretofore substantially increased the cost of the air conditioning unit and controls therefor. Accordingly, some units have not utilized warmup switches, thereby creating occupant discomfort.
  • an air conditioning unit for supplying conditioned air into a space to be conditioned and having means to regulate the quantity of air discharged from the unit.
  • a pressure responsive valve is connected to the air regulating means and to the supply duct to provide a control signal to the air regulating means, the magnitude of the control signal varying with changes in pressure of the conditioned air in the supply duct.
  • Thermostatic means for sensing the temperature of the air in the area being conditioned and for further varying the magnitude of the control signal supplied to the air regulating means operates to decrease the quantity of conditioned air supplied from the unit as the temperature of the area approaches a predetermined value.
  • Means are connected to the thermostatic means and to the pressure responsive valve, the means including a normally open port through which conditioned air passes from the conditioned air supply duct to the pressure'responsive valve, and a normally closed port communicating with the thermostatic means, the normally closed port opening when the temperature of the conditioned air supplied from the central station exceeds a predetermined value.
  • the warm air passes through the port to the thermostatic means, so that the magnitude of the control signal from the pressure responsive valve to the air regulating means is determined solely by the pressure of the conditioned air in the supply duct.
  • FIG. 2 is a partial side elevational view of the air conditioning unit including the present invention.
  • a central air conditioning apparatus including a filter 5, precooling coil 7, spray means 9, cooling coil 11, heating coil 13 and a fan 15, for heating, cool- 3 ing, humidifying and filtering the air as desired, to provide conditioned air for passage to the area being conditioned.
  • a supply air duct 17 is illustrative o a plurality of ducts provided to supply conditioned air to the air conditioning units disposed throughout the building.
  • the air conditioning unit or terminal is illustrated as a ceiling air terminal.
  • air conditioning units for example but notto be limited to, induction units of a type well known to those familiar in the art, may be employed in lieu of the ceiling terminal hereinafter described in detail.
  • the ceiling terminal includes a primary chamber 19 lined with a sound absorbing material 21 such as a glass fiber blanket.
  • the primary chamber is ordinarily open at both ends for connecting a series of terminals end to end to provide a complete air discharge system. Suitable end pieces (not shown) are utilized to cap the end terminals in the series.
  • An air supply distribution plate 23 having a plurality of collared openings 25 therein is provided to evenly distribute supply air from primary chamber 19 into distribution chamber 27 which is defined by the top and side walls of distribution plate 23. To provide an optimum air discharge pattern, the air supplied to the distribution chamber from the primary chamber should have minimal non-vertical velocity components.
  • the collars divert the horizontal velocity component of the air stream from primary chamber 19 so the velocity components of the air stream in distribution chamber 27 are vertical.
  • the bottom of distribution chamber 27 includes aligned cutoff plates 29 which are provided with curved surface 30 for engagement by bladders 31 and 33 to form a damper or control chamber.
  • the curved surfaces smooth the flow of air through the damper to minimize the pressure drop therethrough when the bladder is fully deflated to provide a low noise level over the entire operating range of the terminal as bladder inflation is varied between a fully deflated position and a fully inflated position.
  • Surface 30 is covered with felt 32 to further minimize noise.
  • the area of the opening between the bladders and the cutoff plates may be varied. This feature can be utilized to provide a variety of modes of terminal operation. If it is desired to maintain a constant discharge of air from the terminal, a pressure responsive control 51, illustrated in FIG. 2, may be employed to inflate or deflate the bladders in response to supply air pressure to reduce the area between the bladders and cutoff plates as duct pressure increases and to increase the area therebetween as duct pressure decreases. If it is desired to control the terminal to provide a constant room temperature under varying cooling loads, the bladder inflation may be further controlled by a thermostat 90, illustrated in FIG. 2, responsive to room temperature to provide an increased quantity of air flow from the terminal as the cooling load increases and a decreased quantity of air flow from the terminal as the cooling load decreases.
  • a thermostat 90 illustrated in FIG. 2
  • Bladders 31 and 33 are adhesively mounted on a central partition assembly comprised of opposed generally convex plates 35, diffuser triangle 37 and control module 39.
  • the plates have a V-shaped recess therein so the bladders are completely recessed within the plates when deflated. This provides a large area between the active walls of the bladders and the cutoff plates for 4 maximum air flow therebetween. Further, the recessed bladder provides a smooth surface along plate 35 too minimize air turbulence.
  • the damper mechanism is disposed a substantial distance upstream from the discharge opening in the terminal to provide sufficient space therebetween to absorb any noise generated by the damper mechanism.
  • downwardly extending walls 41 which form air passages in conjunction with paltes 35 are lined with sound absorbing material such as glass fiber blankets 43.
  • Outlet members 45 having outwardly flared lower portions 47 thereof are affixed, as by welding, to walls 41.
  • the air conditioning terminal includes a damper control module assembly including the control of thepresent invention.
  • the module assembly includes convex plates 35, bladders 31 and 33, and a control module 39 mounted on triangular diffuser member 37.
  • the control module preferably comprises filter means 49, a pressureresponsive valve or pressure regulator 51, and thermostat 90.
  • Filter 49 is provided with an opening 54 in a top surface thereof for communication with primary chamber 19.
  • Filter 49 further includes a first, normally opened port 55, disposed in the lower surface thereof. Filtered air from filter 49 is supplied through normally opened port 55 and duct 56 to pressure regulator 51.
  • Filter 49 further includes a second normally closed port 57 disposed in the lower surface thereof.
  • a bimetallic member 59 is movably positioned over port 57 for a reason to be more fully explained hereinafter. Filtered air from filter 49 is supplied to thermostat via port 57 and duct 61 when the bimetallic member 59 moves so as to open port 57, as is illustrated in FIG. 2.
  • thermostat 90 During normal operation, controlled air from pressure regulator 51 is supplied to thermostat 90 and to bladders 31 and 33. If it is desirable to control bladders 31 and 33 independently, the control module may be provided with two filters, two regulators, and two thermostats. This may be desirable when the air terminal is disposed above a room partition for individual temperature control on either side of the partition.
  • pressure regulator 51 is of a type disclosed in U.S. Pat. No. 3,434,409, issued Mar. 25, 1969, in the name of Daniel A. Fragnito. Reference may be made to such patent for a complete description of the pressure regulator or valve.
  • thermostat 90 is of a type disclosed in US. Pat. No. 3,595,475, issued in the name of Daniel Morton. Reference may be made to such patent for a complete description of the thermostat.
  • the air supplied from the central air conditioning apparatus via duct 17 is at a relatively low temperature level to cool the spaces or rooms in the building to desired temperature levels in accordance with the preferences of the individual occupants of such areas.
  • the relatively cold conditioned air compensates for heat developed in such areas by one or more of the following: lights, electric machinery, people, and solar heat introduced as a result of radiation and conduction.
  • the machinery is scribed, are unable to entirely stop the flow of conditioned air into the spaces or rooms served by such units.
  • the continual, minimal flow of conditioned air may eventually reduce the temperature in such areas to an undesirably low temperature level.
  • some occupants thereof may be uncomfortable as a result of such relatively low temperature levels.
  • Overcooling may also result during the time when the spaces are unoccupied for prolonged periods of time for example during the weekend, and the central refrigeration plant is shut down. Such Overcooling results from transmission losses to the outside through the skin of the buildmg.
  • thermostatic means for sensing the temperature of said air in said area being conditioned and for further varying the magnitude of said control signal supplied to said air regulating means, the magnitude of said signal increasing as the temperature of said area approaches a predetermined value to decrease the quantity of conditioned air supplied from said unit to said area;
  • said connecting means including a port having a temperature responsive element provided thereover to normally close said port, means connecting said port to said thermostat means, said temperature responsive element opening said port when the temperature of said conditioned air supplied from said central station exceeds a predetermined value, said relatively warm air passing through said port to said thermostatic means, said thermostatic means thereby decreasing the magnitude of the control signal from said pressure responsive valve to said air regulating means to a value as determined solely by the pressure of said conditioned air in said supply duct.
  • thermostatic means for sensing the temperature of said air in said area being conditioned and for further varying the magnitude of said control signal supplied to said air regulating means to reduce the 7 quantity of air discharged from the unit as the temperature in said area approaches a predetermined value
  • said means connecting said pressure responsive valve to said supply duct including a member having a normally open port, conditioned air passing therethrough to said pressure responsive valve, and a normally closed port connected to said thermostatic means, said normally closed port being open when the temperature of said air supplied from said central station exceeds a predetermined value to pass said relatively warm air to said thermostatic means, said thermostatic means thereby becoming ineffective to vary the magnitude of the control signal from said pressure responsive valve to said air regulating means, the magnitude of said signal being determined solely by the pressure of said conditioned air in said supply duct.
  • a control in accordance with claim 2 wherein said means connecting said pressure responsive valve to said supply duct includes a filter member.
  • An air conditioning unit for supplying conditioned air into a space to be conditioned, the air being cooled to a relatively low temperature level at a central station, said central station being connected to said air conditioning unit through a supply duct, said unit comprising:
  • thermostatic means for sensing the temperature of said air in said area being conditioned and for further varying the magnitude of said control signal supplied to said air regulating means, the magnitude of said control signal approaching a value so the air regulating means decreases the quantity of conditioned air supplied from said unit into said area as the temperature of said area approaches a predetermined value;
  • said means including a normally open port through which conditioned air passes from said supply duct to said pressure responsive valve and a normally closed port communicating with said thermostatic means, said normally closed port opening when the temperature of said conditioned air supplied from said central station through said supply duct exceeds a predetermined value, said relatively warm air passing through said port to said thermostatic means, said thermostatic means thereby becoming ineffective to vary the magnitude of the control signal from said pressure responsive valve to said air regulating means, the magnitude of said signal being determined solely by the pressure of said conditioned air in said supply duct.
  • An air conditioned unit in accordance with claim 8 wherein said normally closed port has a bimetallic element disposed thereover, said bimetallic element moving to open the port when the temperature of the air in the supply duct exceeds a predetermined value.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Duct Arrangements (AREA)
  • Air Conditioning Control Device (AREA)
US00395081A 1973-09-07 1973-09-07 Air conditioning unit and control Expired - Lifetime US3824800A (en)

Priority Applications (11)

Application Number Priority Date Filing Date Title
US00395081A US3824800A (en) 1973-09-07 1973-09-07 Air conditioning unit and control
GB3456774A GB1454199A (en) 1973-09-07 1974-08-06 Air conditioning unit
ZA00745055A ZA745055B (en) 1973-09-07 1974-08-07 Air conditioning unit and control
IT26343/74A IT1019971B (it) 1973-09-07 1974-08-14 Apparecchio e dispositivo di rego lazione per il condizionamento del l aria
CH1117274A CH574587A5 (sv) 1973-09-07 1974-08-15
AU72453/74A AU476323B2 (en) 1973-09-07 1974-08-16 Air conditioning unit and control therefor
DE2442102A DE2442102C3 (de) 1973-09-07 1974-09-03 Vorrichtung zum Einblasen von Luft aus einer Zufuhrleitung in einen Raum
FR7430138A FR2243394B1 (sv) 1973-09-07 1974-09-05
BR7434/74A BR7407434D0 (pt) 1973-09-07 1974-09-06 Controle para uma unidade de ar condicionado
SE7411295A SE408585B (sv) 1973-09-07 1974-09-06 Reglerdon for en luftkonditioneringsapparat
JP49102847A JPS5216343B2 (sv) 1973-09-07 1974-09-06

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00395081A US3824800A (en) 1973-09-07 1973-09-07 Air conditioning unit and control

Publications (1)

Publication Number Publication Date
US3824800A true US3824800A (en) 1974-07-23

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Family Applications (1)

Application Number Title Priority Date Filing Date
US00395081A Expired - Lifetime US3824800A (en) 1973-09-07 1973-09-07 Air conditioning unit and control

Country Status (11)

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US (1) US3824800A (sv)
JP (1) JPS5216343B2 (sv)
AU (1) AU476323B2 (sv)
BR (1) BR7407434D0 (sv)
CH (1) CH574587A5 (sv)
DE (1) DE2442102C3 (sv)
FR (1) FR2243394B1 (sv)
GB (1) GB1454199A (sv)
IT (1) IT1019971B (sv)
SE (1) SE408585B (sv)
ZA (1) ZA745055B (sv)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4238071A (en) * 1979-06-29 1980-12-09 Carrier Corporation Air conditioning system and control therefor
US4298164A (en) * 1979-06-29 1981-11-03 Carrier Corporation Air conditioning system and control therefor
EP0042998A2 (en) * 1980-07-02 1982-01-06 Carrier Corporation Positive shutoff for individual units of a central air conditioning system
EP0229742A2 (en) * 1986-01-06 1987-07-22 Carrier Corporation Warm-up/changeover valve or proximity switch
US4821955A (en) * 1988-01-29 1989-04-18 Acutherm, Ltd. Thermally-powered active master and passive satellite air diffuser system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0138729B1 (en) * 1983-09-02 1991-01-02 Carrier Corporation Air distribution system and method for controlling the same

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2828076A (en) * 1955-08-01 1958-03-25 Honeywell Regulator Co Air conditioning apparatus
US2833298A (en) * 1954-11-12 1958-05-06 Bailey Meter Co Ratio control systems
US2906287A (en) * 1955-09-20 1959-09-29 Buensod Stacey Inc Flow control device
US3037702A (en) * 1960-02-08 1962-06-05 Honeywell Regulator Co Air conditioning apparatus having temperature and pressure control
US3058664A (en) * 1960-12-23 1962-10-16 Honeywell Regulator Co Air conditioning control apparatus having temperature and pressure control
US3117723A (en) * 1961-11-20 1964-01-14 Carrier Corp Air distributing units
US3237860A (en) * 1964-05-21 1966-03-01 Robertson Co H H Dual duct air conditioning system with seasonal changeover means
US3595475A (en) * 1969-08-01 1971-07-27 Carrier Corp Bleed-type thermostat
US3610522A (en) * 1969-01-24 1971-10-05 Krueger Mfg Co Air-conditioning system

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2833298A (en) * 1954-11-12 1958-05-06 Bailey Meter Co Ratio control systems
US2828076A (en) * 1955-08-01 1958-03-25 Honeywell Regulator Co Air conditioning apparatus
US2906287A (en) * 1955-09-20 1959-09-29 Buensod Stacey Inc Flow control device
US3037702A (en) * 1960-02-08 1962-06-05 Honeywell Regulator Co Air conditioning apparatus having temperature and pressure control
US3058664A (en) * 1960-12-23 1962-10-16 Honeywell Regulator Co Air conditioning control apparatus having temperature and pressure control
US3117723A (en) * 1961-11-20 1964-01-14 Carrier Corp Air distributing units
US3237860A (en) * 1964-05-21 1966-03-01 Robertson Co H H Dual duct air conditioning system with seasonal changeover means
US3610522A (en) * 1969-01-24 1971-10-05 Krueger Mfg Co Air-conditioning system
US3595475A (en) * 1969-08-01 1971-07-27 Carrier Corp Bleed-type thermostat

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4238071A (en) * 1979-06-29 1980-12-09 Carrier Corporation Air conditioning system and control therefor
US4298164A (en) * 1979-06-29 1981-11-03 Carrier Corporation Air conditioning system and control therefor
EP0042998A2 (en) * 1980-07-02 1982-01-06 Carrier Corporation Positive shutoff for individual units of a central air conditioning system
EP0042998A3 (en) * 1980-07-02 1982-03-10 Carrier Corporation Positive shutoff for individual units of a central air conditioning system
EP0229742A2 (en) * 1986-01-06 1987-07-22 Carrier Corporation Warm-up/changeover valve or proximity switch
EP0229742A3 (en) * 1986-01-06 1989-02-08 Carrier Corporation Warm-up/changeover valve or proximity switch
EP0414331B1 (en) * 1986-01-06 1992-12-02 Carrier Corporation Changeover arrangement for a central air conditioning unit
US4821955A (en) * 1988-01-29 1989-04-18 Acutherm, Ltd. Thermally-powered active master and passive satellite air diffuser system

Also Published As

Publication number Publication date
DE2442102B2 (de) 1978-03-16
GB1454199A (en) 1976-10-27
BR7407434D0 (pt) 1975-09-09
DE2442102C3 (de) 1978-11-09
SE408585B (sv) 1979-06-18
ZA745055B (en) 1975-08-27
JPS5056043A (sv) 1975-05-16
AU7245374A (en) 1976-02-19
DE2442102A1 (de) 1975-03-13
IT1019971B (it) 1977-11-30
JPS5216343B2 (sv) 1977-05-09
FR2243394A1 (sv) 1975-04-04
SE7411295L (sv) 1975-03-10
AU476323B2 (en) 1976-09-16
CH574587A5 (sv) 1976-04-15
FR2243394B1 (sv) 1976-10-22

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